On Mon, Jun 01, 2015 at 01:00:57PM -0400, Doug Ledford wrote: > > case for this feature, generalizing too much may destroy the > > performance that is valuable here. > I'm not convinced of that. Steve has already spoke up about the > timestamps available in cxgb4. Those are very different and yet still > highly valuable to someone investigating performance of their RDMA > application.
? cxgb4 looks nearly identical to me. There is only one HW time stamp 'cqe_sge_ts', which occurs at some point in the flow, and is written the CQE. The current cycle counter can be read from SGE_TIMESTAMP_LO registers. Same as mlx4, really. The rest is just bookkeeping and logging that doesn't require special verbs support for an app to implement. Jason -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
